These organelles are like the organs in a human and they help the cell stay alive. Each organelle has it's own specific function to help the cell survive. The nucleus of a eukaryotic cell directs the cell's activities and stores DNA. Eukaryotes also have a golgi apparatus that packages and distributes proteins. Hope this helps!
Nicotine, once in the brain, will work specifically on nicotinic receptors in the brain. However, there is a common "addiction" pathway in the brain that pretty much all addictive substances go through.
<span>A law is a theory that has explained a number of observed phenomena, and it has predicted a number of other phenomena which may as yet be unobserved.
In that sense, a law is a theory that has not yet been proven wrong or given rise to any contradictions.
A theory is just a theory until it has been proven true by experiments and observation</span>
